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1.
Length weight relationships (LWR) of five marine fishes were estimated from the Bay of Bengal, Bangladesh. Fish samples were collected occasionally from fisher's catch with gill net (mesh size: 3 cm) during November 2019 to October 2020. Fishing was done overnight. Total length (0.1 cm) and body weight (0.01 g) of each individual were measured. We recorded maximum total length for P. maculatus (55.0 cm) and P. parmatus (39.0 cm).  相似文献   
2.
BackgroundExperiments in isolated perfused heart have shown that heart rate is lower and sinoatrial node (SAN) action potential duration is longer in streptozotocin (STZ)–induced diabetic rat compared to controls. In sino-atrial preparations the pacemaker cycle length and sino-atrial conduction time are prolonged in STZ heart. To further clarify the molecular basis of electrical disturbances in the diabetic heart the profile of mRNA encoding a wide variety of proteins associated with the generation and transmission of electrical activity has been evaluated in the SAN of STZ-induced diabetic rat heart.Conclusions/SignificanceCollectively, this study has demonstrated differences in the profile of mRNA encoding a variety of proteins that are associated with the generation, conduction and regulation of electrical signals in the SAN of STZ-induced diabetic rat heart. Data from this study will provide a basis for a substantial range of future studies to investigate whether these changes in mRNA translate into changes in electrophysiological function.  相似文献   
3.
Bacille Calmette–Guérin (BCG) immunization provides variable protection against tuberculosis. Prenatal antigen exposure may have lifelong effects on responses to related antigens and pathogens. We therefore hypothesized that maternal latent Mycobacterium tuberculosis infection (LTBI) influences infant responses to BCG immunization at birth. We measured antibody (n = 53) and cellular (n = 31) responses to M. tuberculosis purified protein derivative (PPD) in infants of mothers with and without LTBI, in cord blood and at one and six weeks after BCG. The concentrations of PPD-specific antibodies declined between birth (median [interquartile range (IQR)]) 5600 ng ml−1 [3300–11 050] in cord blood) and six weeks (0.00 ng ml−1 [0–288]). Frequencies of PPD-specific IFN-γ-expressing CD4+T cells increased at one week and declined between one and six weeks (p = 0.031). Frequencies of IL-2- and TNF-α-expressing PPD-specific CD4+T cells increased between one and six weeks (p = 0.019, p = 0.009, respectively). At one week, the frequency of PPD-specific CD4+T cells expressing any of the three cytokines, combined, was lower among infants of mothers with LTBI, in crude analyses (p = 0.002) and after adjusting for confounders (mean difference, 95% CI −0.041% (−0.082, −0.001)). In conclusion, maternal LTBI was associated with lower infant anti-mycobacterial T-cell responses immediately following BCG immunization. These findings are being explored further in a larger study.  相似文献   
4.

Background

Helminth infections may modulate immune responses to unrelated pathogens and allergens; these effects may commence prenatally. We addressed the hypothesis that anthelminthic treatment in pregnancy and early childhood would improve responses to immunisation and modulate disease incidence in early childhood with both beneficial and detrimental effects.

Methods and Findings

A randomised, double-blind, placebo-controlled trial was conducted in Entebbe, Uganda [ISRCTN32849447]. In three independent randomisations, 2507 pregnant women were allocated to receive single-dose albendazole or placebo, and praziquantel or placebo; 2016 of their offspring were randomised to receive quarterly single-dose albendazole or placebo from age 15 months to 5 years. Primary outcomes were post-immunisation recall responses to BCG and tetanus antigens, and incidence of malaria, diarrhoea, and pneumonia; incidence of eczema was an important secondary outcome. Analysis was by intention-to-treat. Of 2345 live births, 1622 (69%) children remained in follow-up at age 5 years. 68% of mothers at enrolment, and 11% of five-year-olds, had helminth infections. Maternal hookworm and Schistosoma mansoni were effectively treated by albendazole and praziquantel, respectively; and childhood hookworm and Ascaris by quarterly albendazole. Incidence rates of malaria, diarrhoea, pneumonia, and eczema were 34, 65, 10 and 5 per 100 py, respectively. Albendazole during pregnancy caused an increased rate of eczema in the children (HR 1.58 (95% CI 1.15–2.17), p = 0.005). Quarterly albendazole during childhood was associated with reduced incidence of clinical malaria (HR 0.85 (95% CI 0.73–0.98), p = 0.03). There were no consistent effects of the interventions on any other outcome.

Conclusions

Routine use of albendazole in pregnancy may not always be beneficial, even in tropical developing countries. By contrast, regular albendazole treatment in preschool children may have an additional benefit for malaria control where helminths and malaria are co-endemic. Given the low helminth prevalence in our children, the effect of albendazole on malaria is likely to be direct.

Trial registration

Current Controlled Trials ISRCTN32849447  相似文献   
5.
This paper describes a highly specific and sensitive method for quantifying oxazepam and its diastereoisometric glucuronides in serum. The method involves sample clean-up by solid-phase extraction on C18 cartridge followed by quantitation on a reversed-phase HPLC column. Diazepam is used as internal standard. Extraction recovery from serum proved to be more than 86%. Precision, expressed as C.V., was in the range 1.2–9.5%. The limits of quantification were 40, 400, and 200 nmol/l for oxazepam, S-(+)- and R-(−)-glucuronides, respectively. This method was applied to the determination of oxazepam and its diastereoisometric glucuronides in serum collected during a pharmacokinetic study performed in sheep after oral administration of racemic oxazepam. S-(+)/R-(−) ratios were measured all along the sampling time collection and the pharmacokinetic parameters were determined.  相似文献   
6.

Introduction

Offspring of Schistosoma mansoni-infected women in schistosomiasis-endemic areas may be sensitised in-utero. This may influence their immune responsiveness to schistosome infection and schistosomiasis-associated morbidity. Effects of praziquantel treatment of S. mansoni during pregnancy on risk of S. mansoni infection among offspring, and on their immune responsiveness when they become exposed to S. mansoni, are unknown. Here we examined effects of praziquantel treatment of S. mansoni during pregnancy on prevalence of S. mansoni and immune responsiveness among offspring at age five years.

Methods

In a trial in Uganda (ISRCTN32849447, http://www.controlled-trials.com/ISRCTN32849447/elliott), offspring of women treated with praziquantel or placebo during pregnancy were examined for S. mansoni infection and for cytokine and antibody responses to SWA and SEA, as well as for T cell expression of FoxP3, at age five years.

Results

Of the 1343 children examined, 32 (2.4%) had S. mansoni infection at age five years based on a single stool sample. Infection prevalence did not differ between children of treated or untreated mothers. Cytokine (IFNγ, IL-5, IL-10 and IL-13) and antibody (IgG1, Ig4 and IgE) responses to SWA and SEA, and FoxP3 expression, were higher among infected than uninfected children. Praziquantel treatment of S. mansoni during pregnancy had no effect on immune responses, with the exception of IL-10 responses to SWA, which was higher in offspring of women that received praziquantel during pregnancy than those who did not.

Conclusion

We found no evidence that maternal S. mansoni infection and its treatment during pregnancy influence prevalence and intensity of S. mansoni infection or effector immune response to S. mansoni infection among offspring at age five years, but the observed effects on IL-10 responses to SWA suggest that maternal S. mansoni and its treatment during pregnancy may affect immunoregulatory responsiveness in childhood schistosomiasis. This might have implications for pathogenesis of the disease.  相似文献   
7.
The small leucine-rich proteoglycan decorin has been demonstrated to be a key regulator of collagen fibrillogenesis; decorin deficiencies lead to irregularly shaped collagen fibrils and weakened material behavior in postnatal murine connective tissues. In an in vitro investigation of the contributions of decorin to tissue organization and material behavior, model tissues were engineered by seeding embryonic fibroblasts, harvested from 12.5-13.5 days gestational aged decorin null (Dcn(-/-)) or wild-type mice, within type I collagen gels. The resulting three-dimensional collagen matrices were cultured for 4 weeks under static tension. The collagen matrices seeded with Dcn(-/-) cells exhibited greater contraction, cell density, ultimate tensile strength, and elastic modulus than those seeded with wild-type cells. Ultrastructurally, the matrices seeded with Dcn(-/-) cells contained a greater density of collagen. The decorin-null tissues contained more biglycan than control tissues, suggesting that this related proteoglycan compensated for the absence of decorin. The effect of transforming growth factor-beta (TGF-beta), which is normally sequestered by decorin, was also investigated in this study. The addition of TGF-beta1 to the matrices seeded with wild-type cells improved their contraction and mechanical strength, whereas blocking TGF-beta1 in the Dcn(-/-) cell-seeded matrices significantly reduced the collagen gel contraction. These results indicate that the inhibitory interaction between decorin and TGF-beta1 significantly influenced the matrix organization and material behavior of these in vitro model tissues.  相似文献   
8.
In 1994 and 2002, respectively, the World Health Organisation proposed that treatment for hookworm and schistosomiasis could be provided during pregnancy. It was hoped that this might have benefits for maternal anaemia, fetal growth and perinatal mortality; a beneficial effect on the infant response to immunisation was also hypothesised. Three trials have now been conducted. Two have examined the effects of benzimidazoles; one (the Entebbe Mother and Baby Study) the effects of albendazole and praziquantel. All three were conducted in settings of high prevalence but low intensity helminth infection. Results suggest that, in such settings and given adequate provision of haematinics, the benefit of routine anthelminthics during pregnancy for maternal anaemia may be small; none of the other expected benefits has yet been demonstrated. The Entebbe Mother and Baby Study found a significant adverse effect of albendazole on the incidence of infantile eczema in the whole study population, and of praziquantel on the incidence of eczema among infants of mothers with Schistosoma mansoni. Further studies are required in settings that differ in helminth species and infection intensities. Further research is required to determine whether increased rates of infantile eczema translate to long-term susceptibility to allergy, and to explore the underlying mechanisms of these effects. The risks and benefits of routine anthelminthic treatment in antenatal clinics may need to be reconsidered.  相似文献   
9.
With the increase in average life expectancy and growing aging population, lack of functional grafts for replacement surgeries has become a severe problem. Engineered tissues are a promising alternative to this problem because they can mimic the physiological function of the native tissues and be cultured on demand. Cyclic stretch is important for developing many engineered tissues such as hearts, heart valves, muscles, and bones. Thus a variety of stretch bioreactors and corresponding scaffolds have been designed and tested to study the underlying mechanism of tissue formation and to optimize the mechanical conditions applied to the engineered tissues. In this review, we look at various designs of stretch bioreactors and common scaffolds and offer insights for future improvements in tissue engineering applications. First, we summarize the requirements and common configuration of stretch bioreactors. Next, we present the features of different actuating and motion transforming systems and their applications. Since most bioreactors must measure detailed distributions of loads and deformations on engineered tissues, techniques with high accuracy, precision, and frequency have been developed. We also cover the key points in designing culture chambers, nutrition exchanging systems, and regimens used for specific tissues. Since scaffolds are essential for providing biophysical microenvironments for residing cells, we discuss materials and technologies used in fabricating scaffolds to mimic anisotropic native tissues, including decellularized tissues, hydrogels, biocompatible polymers, electrospinning, and 3D bioprinting techniques. Finally, we present the potential future directions for improving stretch bioreactors and scaffolds. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:543–553, 2016  相似文献   
10.

In this recent era, several approaches have been developed to alleviate the adverse effects of salinity stress in different plants. However, some of them are not eco-friendly. In this context, evolving sustainable approaches which enhance the productivity of saline soil without harming the environment are necessary. Many recent studies showed that plant growth-promoting rhizobacteria (PGPR) are known to confer salinity tolerance to plants. Salt-stressed plants inoculated with PGPR enhance the growth and productivity of crops by reducing oxidative damage, maintaining ionic homeostasis, enhancing antioxidant machinery, and regulating gene expressions. The PGPR also regulates the photosynthetic attributes such as net photosynthetic rate, chlorophyll, and carotenoid contents and enhances the salinity tolerance to plants. Moreover, PGPR has a great role in the enhancement of phytohormones and secondary metabolites synthesis in plants under salt stress. This review summarizes the current reports of the application of PGPR in plants under salt stress and discusses the PGPR-mediated mechanisms in plants of salt tolerance. This review also discusses the potential role of PGPR in cross-talk with phytohormones and secondary metabolites to alleviate salt stress and highlights the research gaps where further research is needed.

  相似文献   
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